How to Control Humidity Inside a Greenhouse

Reading Humidity First

Before adjusting anything, place a Hygrometer inside the greenhouse. It reports the current humidity level so you know whether you need to dry the air or add moisture. Pair it with a Growth Detector if you want to see how the conditions are affecting your plants.

Adding or Removing Moisture

• To raise humidity: place a Wooden Grate Humidifier inside the enclosure. It releases moisture into the air. A Humidity Tank stores water for the humidifier to draw from, so keep it filled.
• To lower humidity: place a Greenhouse Dehumidifier. It pulls excess moisture out of the air, which matters for crops that rot or fail in damp conditions.

Run both only as needed — the Hygrometer tells you which way to go. If humidity swings too far in either direction, add the opposite device and let them balance out. Check the Humidity Tank level periodically; a dry tank means the humidifier stops working and your humidity will drift back down. For crops that need a specific damp or dry range, tune by adding or removing one device at a time and re-reading the Hygrometer after each change.